In the industrial process for producing audio and video tape cassettes, automatic machines which wind tape into cassettes are widely used. In these cases, when high productivity is required, the loading machines are typically supplied with empty cassettes by way of a supply conveyor which brings cassettes into a position in which they can be transferred to the tape loading machine.
In one known system and method, an operator manually deposits a row of cassettes, picked up from a packing tray onto a linear feed conveyor. The output end of the feed conveyor opens perpendicularly onto a supply conveyor such that the cassettes are dropped one after another onto the supply conveyor. The cassettes are then carried to the loading machines on the supply conveyor.
While satisfactory for feeding to cassette loading machines, feed systems and methods of the above type rely on significant manpower to pick up the individual cassette rows from the trays and place them onto the linear feed conveyor. The linear feed conveyor, because of space constraints, generally cannot hold more than two or three cassette rows. When the high production speed reached by loading machines is taken into account, the cassettes on the linear feed conveyor discharged onto the supply conveyor within a very short lapse of time, i.e., as little as one minute or less. The constant presence of one or more operators is therefore necessary to maintain a constant supply of cassettes.
In an attempt to solve this problem, feed units have been conceived in which the linear feed conveyor is vertically rather than horizontally oriented along which a plurality of support and drive elements are distributed. Each of the support and drive elements supports a cassette row to be deposited on the supply conveyor, in order to enable them to be raised towards the output end which is located at a position vertically displaced from the supply conveyor.
The vertically-oriented linear feed conveyor is capable of engaging a greater number of cassette rows than the linear feed conveyor extending horizontally, within the same space. However, this configuration does not eliminate the necessity of an operator since cassette rows still must be manually picked up from the trays and put onto the feed conveyor.
Feeders have also been provided which comprise a turret rotating about a vertical axis, provided with a plurality of circumferentially distributed compartments, capable of engaging one or more cassette rows drawn from a tray. Transfer means, such as a pusher mechanism movable in a radial direction with respect to the turret base, pick up the individual cassettes from one of the engagement compartments disposed in alignment with the output conveyor, to transfer cassettes to the supply conveyor.
When no more cassettes are present in the engagement compartment, the turret is rotated, so that the cassettes in the adjacent compartment can be acted upon by the transfer means.
This solution also involves significant use of manpower. Cassette rows must still be individually picked up from the corresponding trays, and the turret cannot hold a sufficient amount of cassettes to allow for continuous operation for any length of time.